Lasik doesn't eliminate risks of myopia

A girl getting her eyes checked for myopia.
A girl getting her eyes checked for myopia. ST PHOTO: KEVIN LIM

Not everyone can undergo Lasik to correct myopia.

For some people, being very short-sighted could result in a higher risk of having other eye conditions, such as glaucoma, and retinal tears and detachment.

This happened to Mr Carl Hui, 42, when he went to the Singapore National Eye Centre (SNEC) in 2004 to check if he could have Lasik done.The engineering consultant had myopia of about 1,000 degrees in both eyes.

Instead, he found out that he was already suffering from glaucoma, a condition characterised by progressive damage to the optic nerve that leads to blind spots in one's visual field. If the disease is severe, the central vision can be wiped out, causing permanent blindness.

Lasik was out of the question for Mr Hui as the procedure is not advised for people with glaucoma.

In fact, treating myopia with Lasik does not reduce the potential complications related to myopia. Glaucoma can still occur in a patient who has undergone Lasik, said Assistant Professor Mohamad Rosman, who heads SNEC's refractive surgery department and Laser Vision Centre.

But diagnosing this condition in those with myopia has its challenges, said Adjunct Associate Professor Ho Ching Lin. It may occur at relatively normal eye pressures in those with myopia, which can make detection difficult, said the senior consultant and head (clinical service) of SNEC's glaucoma department.

With Singapore's rising myopia rate and prevalence of glaucoma, which is projected to increase as the population ages, Prof Ho said there is an urgency to educate Singaporeans to have their eyes checked earlier. Anyone above 40 is at risk of glaucoma and should go for eye check-ups, such as once a year or every two years, said Prof Rosman. Someone who has undergone Lasik is no exception.

The only problem is that the commonly used screening method for glaucoma, which involves measuring intraocular pressure, is not accurate in people who have undergone Lasik. They may need to be screened using other methods, said Prof Rosman.

 Vision loss from glaucoma can then be limited or slowed with early diagnosis and treatment.

Ideally, myopia prevention should start early with good eye habits, such as doing less near work, taking breaks and taking part in more outdoor activities, said Prof Rosman.

For children with increasing myopia, atropine eye drops (which relax the muscles in the eyes) can help to slow down the rate at which myopia is worsening.

Since he found out he has glaucoma, Mr Hui uses eye drops regularly and takes frequent breaks from looking at the computer.

His myopia has stabilised at around 1,100 degrees and his glaucoma has been slowed down.

"Wearing spectacles may be inconvenient, but it is better than slowly becoming blind," he said.

Ng Wan Ching

A version of this article appeared in the print edition of The Straits Times on January 19, 2016, with the headline 'Lasik doesn't eliminate risks of myopia'. Print Edition | Subscribe